Please do contribute if you can.
This is a candidate to replace the current rfid solution at hackrva.
If you are interested in contributing, I can bring some spare mcus and readers to hackrva.
The main problem this is trying to solve is that there's no verification step between the server and the current rfid reader.
When someone scans their rfid fob, the mcu will compare it to the ACL (access control list) that it currently has stored.
Access Granted -> activate the relay. -> log the event Access Denied -> log the event
TODO: add some notes on setting up dev environment -- it's similar to badge
Essentially:
- disconnect the Board
- hold down BOOTSEL button
- connect the Board
bash run_cmake.sh # you should only have to run this the first time
cd build
makecopy the firmware to the Board
cp hack_rfid.uf2 /media/$USER/RPI-RP2/| feature | status |
|---|---|
| hashable ACL | ✅ |
| rfid reader | ✅ |
| persistent storage | ❌ |
| network (wifi) | ❌ |
| update mechanism (mqtt events) | ❌ |
- rpi pico w
- mfrc522 rfid reader
- 1591B Relay Board
12v power supply
note: there's some interest in switching to pn532 for the rfid reader
The rfid reader will subscribe to specific mqtt events so that the server can report changes to the ACL. The server should be able to request the current ACL hash to determine if the reader holds an ACL that is out dated. If the ACL is outdated, the server should initiate a sync.
The mcu should publish events and heartbeats via mqtt.
The Raspberry Pi Pico connects to the RC522 module via the SPI interface. The default pinouts are provided below:
| RFID Signal | Pico Pin |
|---|---|
| SCK | GP2 |
| MOSI | GP3 |
| MISO | GP4 |
| RST | GP0 |
| SDA | GP1 |
note: pin TBD
mqtt is currently not implemented. However the existing mqtt topics are as follows:
| Topic | Payload | Notes |
|---|---|---|
<topic_prefix>/acl |
n/a | The device will publish a <topic_prefix>/acl_response message. |
<topic_prefix>/adduser |
uid of the RFID fob to add |
Adds the specified fob to the device's Access Control List (ACL). |
<topic_prefix>/removeuser |
uid of the RFID fob to remove |
Removes the specified fob from the device's ACL. |
<topic_prefix>/open |
n/a | Opens the door. |
| Topic | Payload | Notes |
|---|---|---|
<topic_prefix>/acl_response |
{'acl': '<SHA256 hash of the current ACL stored>'} |
Allows the server to verify if the device has the correct ACL. |
<topic_prefix>/heartbeat |
OK |
Allows the server to verify the device's network connection. |
<topic_prefix>/access_granted |
uid of the fob that is granted access |
Used for logging purposes. |
<topic_prefix>/access_denied |
uid of the fob that is denied access |
Used for logging purposes. |